Katy joins a host of famous faces, including Paris Hilton, who have descended on the LA event.

Russell Brand's estranged wife was seen bopping along with the commoners in the mosh pit for M83.

Katy has enjoyed detaching herself from reality for the weekend, by dressing up as other people.

Don't ruin your vocal chords! Katy prepares to light a cigarette as she chats to a male companion

On the first day of the festival,
which kicked off on Friday, she channelled her inner goth by copying
teenage witches from another film classic and also Brittany Murphy's
scruffy character from Clueless.